The objective of this research is to examine mechanisms for protein secretion in bacteria. Pulse labeling of pBR322 beta-lactamase will be used to examne the conversion of pre-beta-lactamase to the two mature forms in E. coli. "Precursors" and mature forms will be characterized with respect to NH2-terminal amino acid sequence and effect of various treatments and reagents. Similar analyses of alpha-amylase secretion will be conducted with B. subtilis. Cloned E. coli rbs P plus will be mapped using restriction endonucleases and DNA sequence analysis of the 5'-end initiated to examine the control region and NH2-terminal signal sequence of the protein.